Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

2004

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 3301 - 3330 of 4447

Full-Text Articles in Physical Sciences and Mathematics

Investigation Of Implementation Techniques For Backpropagation Neural Networks., John Culloty Jan 2004

Investigation Of Implementation Techniques For Backpropagation Neural Networks., John Culloty

Theses

Artificial neural networks are biologically inspired computational methods that have the ability to approximate discrete, real and vector valued target functions. For some problem domains this ability makes neural networks a more appealing solution than traditional computational techniques. Such problem domains typically contain a large number of parameters that are interrelated in a complex and often unknown manner. This makes rule based solutions all but impossible. However another feature of such problem domains is the presence of large volumes of real world data that can be used to tram a neural network until it learns the solution.

One of the …


A Toolkit For Xml-Based And Process-Oriented Application Integration, Volker Münch Jan 2004

A Toolkit For Xml-Based And Process-Oriented Application Integration, Volker Münch

Theses

Systems integration is hard work; different architectures with different interfaces and an innumerable amount of Legacy applications with non-standard interfaces exist. However the needs to meet changing business requirements and to implement faster and optimised procedures within an enterprise and in cooperation with other external enterprises mean that there is a continuing demand for such integration strategies and products. Integration was often an activity separate from system development and could not be accomplished without re-involving system designers and developers. Such a process is therefore inefficient and costly. This thesis proposes a process-oriented integration strategy that combines the tasks of integration …


Investigation Of Implementation Techniques For Backpropagation Neural Networks, John Culloty Jan 2004

Investigation Of Implementation Techniques For Backpropagation Neural Networks, John Culloty

Theses

Artificial neural networks are biologically inspired computational methods that have the ability to approximate discrete, real and vector valued target functions. For some problem domains this ability makes neural networks a more appealing solution than traditional computational techniques. Such problem domains typically contain a large number of parameters that are interrelated in a complex and often unknown manner. This makes rule based solutions all but impossible. However another feature of such problem domains is the presence of large volumes of real world data that can be used to tram a neural network until it learns the solution.

One of the …


Development Of Electrochemical Sensors For Monitoring Glucose, Michael Nesbitt Jan 2004

Development Of Electrochemical Sensors For Monitoring Glucose, Michael Nesbitt

Theses

The thesis focuses on evaluating calcium alginate as an immobilisation matrix for the oxidase enzyme glucose oxidase for the amperometric determination of glucose. The basic principles of enzymology and enzyme immobilisation is discussed followed by a review of a variety of first, second and third generation type enzyme electrodes. Amperometry as governed by the Cottrell equation and mass transfer models relating to amperometric electrodes are also considered.

Bovine serum albumin (BSA / GOx) enzyme electrode system was employed as a model to evaluate a calcium alginate immobilisation technique for glucose oxidase. The principal methods employed for enzyme immobilisation were:

• …


A Proposal To Meet The Biofuels Directive In Ireland, Karl Mccarthy Jan 2004

A Proposal To Meet The Biofuels Directive In Ireland, Karl Mccarthy

Theses

In 1990 the transport sector accounted for 9,5% of all Irish emissions. By 2010 it is predicted that transport emissions will have increased by 179%, accounting for 18.8% of all emissions. It is predicted that transport emissions will therefore be around 14,000 kt in 2010. This equates to around €370 million pa in carbon taxes if and when the taxation regime is introduced. This €370 million may be used to facilitate a biofuel industry (for example, by reducing excise duty on biofuels).

The proposed carbon tax along with the EU Biofuels Directive aims to encourage the use of renewable transport …


The Synthesis And Characterisation Of Diiron And Triiron Carbonyl Cluster Compounds With Sulphur And Phosphine Ligands, Geraldine Gray Jan 2004

The Synthesis And Characterisation Of Diiron And Triiron Carbonyl Cluster Compounds With Sulphur And Phosphine Ligands, Geraldine Gray

Theses

This work is primarily concerned with the synthesis and characterisation of di and triiron carbonyl cluster derivatives which contain sulphur and phosphine ligands.

The first chapter is a review of the literature of such complexes. Included are diiron carbonyl clusters which contain phosphine ligands, those which contain sulphur, and those that contain phosphine and sulphur ligands. Triiron carbonyl clusters which contain phosphine ligands, sulphur ligands and both are also discussed.

Chapter two describes the synthesis of compounds of the type [{Fe2(SR)2(CO)5)2Ph2P (CH2)nPPh2] (R = …


Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang Jan 2004

Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang

Electronic Theses and Dissertations

Magnetic materials are currently being developed in the areas of pharmacology and medicinal chemistry for use in applications such as drug delivery and magnetic resonance imaging. Magnetic fluids are being used in audio equipment and hard disk drives. Their suspension in a particular fluid is promoted by the adsorption or reaction of steric or electrostatic stabilizers, which are appropriate for the particular medium. Critical to the success of these magnetic fluids is the development of the steric stabilizers, which must prevent the coagulation of the metal particles. Polymeric materials are one of the most suitable nonmagnetic media to disperse the …


Forecasting The Equity Premium In The Australian Market, David E. Allen, Lurion Demello Jan 2004

Forecasting The Equity Premium In The Australian Market, David E. Allen, Lurion Demello

Research outputs pre 2011

This paper provides a forecasting methodology for estimating the market risk premium in Australia. We employ an in-sample and out-of-sample forecast estimate using various dividend yield measures. The lagged dividend yield model is used to predict future equity premia on a data series that includes the top 85 percent of the Australian stock market. An important concern in this paper is the accuracy of dividend yield in forecasting the equity premium in the Australian market. We find that the level of predictability in the later part of the series is very weak compared to in-sample prediction during the 70s and …


Petrography Of Lower Cretaceous Sandstones On Spitsbergen, Harmon D. Maher Jr., Troy Hays, Robert Duncan Shuster, Jeremy Mutrux Jan 2004

Petrography Of Lower Cretaceous Sandstones On Spitsbergen, Harmon D. Maher Jr., Troy Hays, Robert Duncan Shuster, Jeremy Mutrux

Geography and Geology Faculty Publications

The sandstone petrography of sample suites from four sites spanning the Rurikfjellet (Hauterivian) to Carolinefjellet (Aptian–Albian) formations in central Spitsbergen was investigated. The sandstones show a distinct stepwise shift in composition from quartz arenites to sublitharenites and lithic arenites, typically within the upper part of the Helvetiafjellet Formation. This shift is related to the introduction of 10 - 25 % (grain %) plagioclase grains and volcanic lithics, and a notable increase in basement and sedimentary lithics. Quartz grain character also changes, and grain shapes become more varied. The shift is also associated with the transgressive arrival of marine sediments in …


Assessing Sources And Ages Of Organic Matter Supporting River And Estuarine Bacterial Production: A Multiple-Isotope (D14c, D13c, And D15n) Approach, S. Leigh Mccallister, James E. Bauer, J Cherrier, Hugh W. Ducklow Jan 2004

Assessing Sources And Ages Of Organic Matter Supporting River And Estuarine Bacterial Production: A Multiple-Isotope (D14c, D13c, And D15n) Approach, S. Leigh Mccallister, James E. Bauer, J Cherrier, Hugh W. Ducklow

VIMS Articles

We used radiocarbon (D14C) and stable isotopic (d13C, d15N) signatures of bacterial nucleic acids to estimate the sources and ages of organic matter (OM) assimilated by bacteria in the Hudson River and York River estuary. Dualisotope plots of D14C and d13C coupled with a three-source mixing model resolved the major OM sources supporting bacterial biomass production (BBP). However, overlap in the stable isotopic (d13C and d15N) values of potential source end members (i.e., terrestrial, freshwater phytoplankton, and marsh-derived) prohibited unequivocal source assignments for certain samples. In freshwater regions of the York, terrigenous material of relatively recent origin (i.e., decadal in …


Response Of Dark-Adapted Retinal Rod Photoreceptors, H. Khanal, V. Alexiades, E. Dibenedetto Jan 2004

Response Of Dark-Adapted Retinal Rod Photoreceptors, H. Khanal, V. Alexiades, E. Dibenedetto

Publications

The process of phototransduction, whereby light is converted into an electrical response, in rod and cone photoreceptors in the retina, involves as a key setp, the diffusion of the cytoplasmic, signaling molecules cGMP (cyclic guanosime monophosphate) and Ca2+ diffuse in the cytoplasm (the fluid surrounding the discs). the complex geometry of the rod creates computational difficulties. We present spatio-temporal compuational models for interacctions and diffusion of cGMP and Ca2+ in the cytoplasm of vertebrate rod photoreceptors, as well as numerical simulations fo the response to light of dark-adapted Salamander rods.


Move To Component Based Architectures: Introducing Microsoft's .Net Platform Into The College Classroom, Meg C. Murray Jan 2004

Move To Component Based Architectures: Introducing Microsoft's .Net Platform Into The College Classroom, Meg C. Murray

Faculty Articles

A transformation has been occurring in the architectural model for computer-based application intense software systems. This new model, software-as-a-service, will have a profound impact on the design and development of software for many years to come and as such college level computing curriculums will need to incorporate the concepts and methodologies associated with this new architecture. The platform is built upon a view of interrelated, distributed peer-level software modules and components that work in tandem to achieve specified functional goals. From Microsoft's viewpoint, migration to the new platform requires a radical shift in the software development lifecycle. It is becoming …


A Syntactic Parser With Semantic Filtering For Biomedical Text, Gondy Leroy, Thomas C. Rindflesch, Bisharah Libbus, Halil Kilicoglu, Hsinchun Chen Jan 2004

A Syntactic Parser With Semantic Filtering For Biomedical Text, Gondy Leroy, Thomas C. Rindflesch, Bisharah Libbus, Halil Kilicoglu, Hsinchun Chen

CGU Faculty Publications and Research

No abstract provided.


Using Symbolic Knowledge In The Umls To Disambiguate Words In Small Datasets With A Naive Bayes Classifier, Gondy Leroy, Thomas C. Rindflesch Jan 2004

Using Symbolic Knowledge In The Umls To Disambiguate Words In Small Datasets With A Naive Bayes Classifier, Gondy Leroy, Thomas C. Rindflesch

CGU Faculty Publications and Research

Current approaches to word sense disambiguation use and combine various machine-learning techniques. Most refer to characteristics of the ambiguous word and surrounding words and are based on hundreds of examples. Unfortunately, developing large training sets is time-consuming. We investigate the use of symbolic knowledge to augment machine-learning techniques for small datasets. UMLS semantic types assigned to concepts found in the sentence and relationships between these semantic types form the knowledge base. A naïve Bayes classifier was trained for 15 words with 100 examples for each. The most frequent sense of a word served as the baseline. The effect of increasingly …


Cr Approximation On A Nonrigid Hypersurface Graph In Cⁿ, Al Boggess, Roman Dwilewicz Jan 2004

Cr Approximation On A Nonrigid Hypersurface Graph In Cⁿ, Al Boggess, Roman Dwilewicz

Mathematics and Statistics Faculty Research & Creative Works

Let M be a hypersurface in Cn that is the graph over a (2n - 1)-linear real space. the main result of the paper is that any CR function on M can be uniformly approximated on compact subsets by entire functions on Cn.


Generalized Geologic Map For Land-Use Planning: Lyon County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2004

Generalized Geologic Map For Land-Use Planning: Lyon County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Graves County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2004

Generalized Geologic Map For Land-Use Planning: Graves County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Anderson County, Kentucky, Daniel I. Carey, Martin C. Noger Jan 2004

Generalized Geologic Map For Land-Use Planning: Anderson County, Kentucky, Daniel I. Carey, Martin C. Noger

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Calloway County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2004

Generalized Geologic Map For Land-Use Planning: Calloway County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Mclean County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2004

Generalized Geologic Map For Land-Use Planning: Mclean County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Carlisle County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey Jan 2004

Generalized Geologic Map For Land-Use Planning: Carlisle County, Kentucky, E. Glynn Beck, David A. Williams, Daniel I. Carey

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Generalized Geologic Map For Land-Use Planning: Jefferson County, Kentucky, Bart Davidson, Daniel I. Carey, Stephen F. Greb, Preston S. Lacy Jan 2004

Generalized Geologic Map For Land-Use Planning: Jefferson County, Kentucky, Bart Davidson, Daniel I. Carey, Stephen F. Greb, Preston S. Lacy

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Compartmentalization Of Prion Isoforms Within The Reproductive Tract Of The Ram, Heath W. Ecroyd, Pierre Sarradin, Jean-Louis Dacheux, Jean-Luc Gatti Jan 2004

Compartmentalization Of Prion Isoforms Within The Reproductive Tract Of The Ram, Heath W. Ecroyd, Pierre Sarradin, Jean-Louis Dacheux, Jean-Luc Gatti

Faculty of Science - Papers (Archive)

Cellular prion protein (Prp(C)) is a glycoprotein usually associated with membranes via its glycosylphosphatidylinositol (GPI) anchor. The trans-conformational form of this protein (Prp(SC)) is the suggested agent responsible for transmissible neurodegenerative spongiform encephalopathies. This protein has been shown on sperm and in the reproductive fluids of males. Antibodies directed against the C-terminal sequence near the GPI-anchor site, an N-terminal sequence, and against the whole protein showed that the Prp isoforms were compartmentalized within the reproductive tract of the ram. Immunoblotting with the three antibodies showed that the complete protein and both N- and C-terminally truncated and glycosylated isoforms are present …


The Development Of Signal Transduction Pathways During Epididymal Maturation Is Calcium Dependent, Heath W. Ecroyd, Kelly Asquith, Russell C. Jones, Robert J. Aitken Jan 2004

The Development Of Signal Transduction Pathways During Epididymal Maturation Is Calcium Dependent, Heath W. Ecroyd, Kelly Asquith, Russell C. Jones, Robert J. Aitken

Faculty of Science - Papers (Archive)

Capacitation has been correlated with the activation of a cAMP-PKA-dependent signaling pathway leading to protein tyrosine phosphorylation. The ability to exhibit this response to cAMP matures during epididymal maturation in concert with the ability of the sperrnatozoa to capacitate. In this study, we have addressed the mechanisms by which spermatozoa gain the potential to activate this signaling pathway during epididymal maturation. In a modified Tyrode's medium containing 1.7 mM calcium, caput spermatozoa had significantly higher [Ca2+](i) than caudal cells and could not tyrosine phosphorylate in response to cAMP. However, in calcium-depleted medium both caput and caudal cells could exhibit a …


Negotiating Nature: Collaboration And Conflict Between Aboriginal And Conservation Interests In New South Wales, Australia, Michael Adams Jan 2004

Negotiating Nature: Collaboration And Conflict Between Aboriginal And Conservation Interests In New South Wales, Australia, Michael Adams

Faculty of Science - Papers (Archive)

Faced with the paradox of a large global increase in conservation reserves and a simultaneous global decrease in actual effective protection for biodiversity, conservation scientists and policymakers are questioning established conservation theory and practice. I argue that the fundamental premises, the foundational myths, for Western-style conservation also need to be questioned. The statistics on Indigenous land claims, and conservation reserves, in Australia and more specifically the state of New South Wales (NSW), reveal a landscape of policy failure in both arenas. Focusing on Australia, I use spatial analysis and policy histories to demonstrate converging trajectories of land use priorities for …


Land-Based Activities And Impacts On Coral Reefs And The Marine Environment Of The Pacific Islands, Robert John Morrison, N. S. Tuivavalagi Jan 2004

Land-Based Activities And Impacts On Coral Reefs And The Marine Environment Of The Pacific Islands, Robert John Morrison, N. S. Tuivavalagi

Faculty of Science - Papers (Archive)

This paper recognizes the fact some of the problems encountered in the coral reefs and marine environment of the Pacific are actually due to land-based activities. This message needs to be clearly brought to the attention of farmers and others who work the land - as well as to fishermen and others whose activities focus on coral reefs and the marine environment.

The paper discusses the Pacific environment and some relevant key issues. The paper goes on to discuss land-based activities that harm the coral reef environment - with some emphasis on agricultural activities and soil erosion; however, the impacts …


Charge-On-Spring Polarizable Water Models Revisited: From Water Clusters To Liquid Water To Ice, Haibo Yu, Wilfred Van Gunsteren Jan 2004

Charge-On-Spring Polarizable Water Models Revisited: From Water Clusters To Liquid Water To Ice, Haibo Yu, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

The properties of two improved versions of charge-on-spring �COS� polarizable water models (COS/G2 and COS/G3) that explicitly include nonadditive polarization effects are reported. In COS models, the polarization is represented via a self-consistently induced dipole moment consisting of a pair of separated charges. A previous polarizable water model (COS/B2), upon which the improved versions are based, was developed by Yu, Hansson, and van Gunsteren �J. Chem. Phys. 118, 221 �2003��. To improve the COS/B2 model, which overestimated the dielectric permittivity, one additional virtual atomic site was used to reproduce the water monomer quadrupole moments besides the water monomer dipole moment …


Molecular Dynamics Simulations Of Peptides Containing An Unnatural Amino Acid: Dimerization, Folding, And Protein Binding, Haibo Yu, Xavier Daura, Wilfred Van Gunsteren Jan 2004

Molecular Dynamics Simulations Of Peptides Containing An Unnatural Amino Acid: Dimerization, Folding, And Protein Binding, Haibo Yu, Xavier Daura, Wilfred Van Gunsteren

Faculty of Science - Papers (Archive)

We have performed molecular dynamics (MD) simulations to study the dimerization, folding, and binding to a protein of peptides containing an unnatural amino acid. NMR studies have shown that the substitution of one residue in a tripeptide β-strand by the unnatural amino acid Hao (5-HO2CCONH-2-MeO-C6H3-CO-NHNH2) modifies the conformational flexibility of the β-strand and the hydrogen-bonding properties of its two edges: The number of hydrogen-bond donors and acceptors increases at one edge, whereas at the other, they are sterically hindered. In simulations in chloroform, the Hao-containing peptide 9 (i-PrCO-Phe-Hao-Val-NHBu) forms a β-sheet–like hydrogen-bonded dimer, in good agreement with the available experimental …


Western Pacific Coral Delta18o Records Of Anomalous Holocene Variability In El Nino-Southern Oscillation, Helen V. Mcgregor, M Gagan Jan 2004

Western Pacific Coral Delta18o Records Of Anomalous Holocene Variability In El Nino-Southern Oscillation, Helen V. Mcgregor, M Gagan

Faculty of Science - Papers (Archive)

No abstract provided.


Processes Controlling Metal Transport And Retention As Metal-Contaminated Groundwaters Efflux Through Estuarine Sediments, Stuart L. Simpson, Edward J. Maher, Dianne F. Jolley Jan 2004

Processes Controlling Metal Transport And Retention As Metal-Contaminated Groundwaters Efflux Through Estuarine Sediments, Stuart L. Simpson, Edward J. Maher, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Factors affecting the transport and retention of Cd, Cr, Cu, Ni, Pb and Zn in acidic groundwaters as they pass through estuarine sediments were investigated using column experiments. Acidic groundwaters caused the rapid dissolution of iron sulfide (AVS) and other iron and manganese phases from sediments that are important for metal binding and buffering. Metal breakthrough to overlying water occurred in the order of Ni>Zn>Cd>>Cu>>Cr/Pb. Metal transport increased as the sediment permeability increased, reflecting the low resistance to flow caused by larger sand-sized particles and the decreased abundance of metal adsorption sites on these materials. Metal …